I use an old zenith splitter unit on my K5 with a 35m-M lens. Works just fine. For a viewer see the Owl viewer on http://www.londonstereo.com/shop_home3.html . Also on this site is stereo sets by Brian May (Queen) among others.

Why not have a word with Alan Marlow. See www.cam-rep.co.uk He is really excellent at repairs and charges reasonable prices, as I am sure many members will attest.

Sigma 150-500 on sale at SRS for £649 (with 3yrs warranty) and £100 cash back from Sigma. May be out of your price range but seems to a good deal at total of £549 for anyone with the dosh!

Kit arrived safely. Excellent condition looks almost unused! Looking forward to playing. Thanks Eugene for a great deal.

There is a beta version of PK-Tether that supports tethering of the K3 but with a few of the functions (ISO for example) not working. Tomasz Kos, the author of PK has supplied me with a copy which I am happy to pass on to anyone who wants to try it with K3. PM me if you want a copy. One small request if anyone wants a copy of the beta and finds it is useful please contribute a few £'s to Tomasz via Paypal on his website www.pktether.com. Tomasz does not yet have his own K3 so is developing on a friends. May be if users fund him a bit he may get his own K3 and develop a fully functioning version for K3.

I use old Mamiya 645 quick release heads, the all metal type as pictured below. Very substantial, holds my 150-500mm Sigma really safely and they have a secondary locking mechanism. These often turn up on fleabay for £10 -20.

Just in case anyone missed Chris's post Sigma 150-500mm for £649 at http://www.srsmicrosystems.co.uk/ PLUS £100 cashback from Sigma! Can't be bad.

Great people to deal with and good prices on filters. Very fast delivery.
http://www.crookedimaging.co.uk

Yes mine came from Germany. I trimmed 2mm off end of protector so it would lay flat. No problems with bubbles. I have the non reflective type which do not appears to make LCD view grainy.

I've got the Folix anti reflection screen protector. Kit comes with 3 sets of pre- cut Foils for both lcd's. Look on Amazon for "atFoliX FX-Antireflex screen-protector for Ricoh Pentax K-3 (3 pack) - Anti-reflective screen protection!"