If you just replaced your filter these filters on eBay must look familiar.
VW/Jetta etc...
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2411626371&category=33662
Audi 5000/100/200&turbo...
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2411028264&category=33662
same as the 944's or what?
For less than $60 you can get a transmission 'Master' kit which includes: "Paper gaskets, rubber lip seals, O rings, pan gasket, metal clad seals, sealing ring kit (metal or teflon sealing rings depending on unit) Friction clutch plates and Steel clutch plates"...see:
http://www.bulkpart.com/cgi-bin/miva?Merchant2/merchant.mv+Screen=PROD&Store_Code=MDITP&Product_Code=71002
And the 010 rebuild manual is about $16.
It looks like there are are only 4 nuts holding the 010 tranny section to the final drive (diff) section. So maybe any 010 tranny (audi/vw whatever) would mate to the final drive? (Just some posibilites.)