YERTIS http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&category=15240&item=7520046096&rd=1&ssPageName=WDVW

Might plonk on a bid myself

It's ................... oh no, that's mine - sorry

I'm sure there were quite a few MZ series cameras a while ago but not many at the moment

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&category=15240&item=7519023818&rd=1

or there's a KX outfit (costly postage)

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&category=11720&item=7519662119&rd=1&ssPageName=WDVW

or this one, says UK only but might be worth asking

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&category=15215&item=7520423316&rd=1&ssPageName=WDVW

Apologies David, just checked eBay's US site and I must admit that there doesn't seem to be a great deal available but plenty worldwide!

I don't think there's much to choose between the KM and KX but I do like the pentaprism window on the KX (like on the MX) that allows you to see the aperture ring setting.

Older camera gear is great to collect but K series cameras won't do anything that your SFXn can't do - I thought you wanted a modern camera with up to date metering, and I still think you'd find an MZ3 or 5n within your budget.
It's a pity that Pentax didn't (or haven't yet) produced a manual only camera with sophisticated metering options, extensive shutter speeds and built in flash - something along the lines of the Canon T90 perhaps, but they haven't and your choice is limited to the OK-ish MZ-M or the others already mentioned.

David,

The MZ3 and MZ5n are almost identical: Multi-pattern (matrix) metering, DoF preview, built in flash, film winder and manual focussing when required. Both are small, light weight and incredibly robust and have top plate dials (exactly what you are asking for).
Older manual focus only bodies do not have the advanced metering options, they were smaller and lighter than your SFXn because they did not have built in motor drives, focus motors or flash units.
Things have moved on a long way since the SFX era and modern cameras have all the automation but are about the same size and weight as the older manual cameras.
35mm SLRs have never been available so cheaply and there are a number of potential bargains on eBay, it's impossible to give a value these days but you should definately find something within your budget.

David,

I've no personal experience of the ZX-M (MZ-M over here) but I think you'd probably be better off with something like an MZ5n.
The SFX has single point focussing and average (centre-weighted) metering whereas the MZ-M has two zone metering and is better able to deal with backlit situations but it is still fairly basic.
The MZ5 is of a similar design and size/weight but much more sophisticated (six-segment / spot metering and 3 point AF) and being an AF camera, you'll have the option for fully manual operation and the full use of your AF lenses whenever you wish.
The MZ5n also has a built-in flash (like the SFX), which at times can be invaluable.

Have a browse through the manuals on Kim's site and see what you think:
http://www.pentax-manuals.com/

Fair enough John, remarkable results for the 750Z - another Pentax triumph!

Excellent work John, most interesting.
I wonder if it might have been an idea to have chosen the same resolution rather than the maximum for each camera ie. 3MP un-interpolated?

Well, before investing in a seperate meter, I'd be inclined to try an 18% grey card. These are very cheap and enable you to obtain very accurate readings from your camera's meter.
There's nothing wrong with the meter in the P30 but it is centre-weighted and susceptible to errors caused by excessively bright or dark areas within the frame. If you expose from an area that is roughly equivalent to 18% grey ie. green grass (illuminated by the same light that is falling on the subject) or a good blue sky, store the settings and then recompose to include the subject the result should be spot on.
Using an 18% grey card means that you don't have to fill the frame with a suitable subject - you simply hold the card in the light that is falling on the subject and meter directly from the card.
With a little practise it is a cheap and foolproof method and quicker than using a hand-held meter whose readings you then have to transfer to the camera.