You could try giving Damian McGillicuddy a ring. He supplies his own beauty dish so might be able to help or point you in the right direction.

As Bill highlights really, if upgrading is the objective of course we have to move onwards and upwards. If the purpose was to do this, then a K-5 for general use, plus hanging on to the K-r for a while as a spare just in case, is an alternative plan.

I say the K-5 as the price is very keen again just now and this is the best time to buy it new.

Whatever advice we give, it all depends on the game plan of the OP.

I have always tried to make the second body the same as the first. For yourself, that would suggest another K-r.

That way, there are identical controls, so no confusion, identical batteries and other accessories. If you have two different types of body you may well prefer one to the other and consequently that will be used allo the time. The second one could become relatively redundant.

New K-r cameras can still be found. Perhapd SRS still have some purple ones left!

The 21mm Limited would be the classic focal length, approaching 35mm on film. Alternatively, if you think Cartier-Bresson, then the 35mm f2.4 is the one, close to 50mm on film.

New this is around £170, but second hand you might be lucky and approach your target figure.

There are plenty of other 35mm lenses in Pentax AF, but they don't tend to crop up very often.

Thinking back to the contemporary reviews of lenses, Fujinons were good but not rising to the same standards as Pentax, Nikon, Canon and Minolta.

Didn't Kodak sell their sensor business to somebody?

Depending on the camera, Shade is another useful option. Different marques have different characteristics too. Fortunately Pentax is very good for colour.

The requirement is probably "best value", which is a combination of all factors, including convenience, service, price...

First the WB fine tune. Custom menu C2 - WB adjustable range. Switch this off and the WB will be fixed.

Now why Daylight WB. Let's take an extreme example. Suppose we have a red sunset. If we use daylight it will be red. If we use AWB the one colour will make the camera want to compensate and dilute the effect.

I use daylight because I use the colour of ambient light and want to retain its qualities. Don't forget that when we used film, daylight film was a fixed WB too. If I want a warmer result (81A filter) then I set Cloudy. If I have very mixed lighting then I might use AWB. In tungsten light I might well use Tungsten setting, just as I would have bought a tungsten film.

Yes, it sounds like sticky diaphragm blades. Unless the engineers find it's something else.

It's worth repairing as it's a fine and expensive lens. Why not join PU Plus and go to JPS, taking advantage of the 20% discount?