Sadly, I have no gear for 10GHz. I think there was a 10GHz contest on Sunday afternoon. I have thought about getting something, also for 1296MHz /P. If I was fitter I might have got "my arse into gear" sooner. As it is, I guess one can only do so much in our great hobby, especially if fitness is a thing of the past!
There is a quite low cost 1296MHz 2W transverter available from Bulgaria (SG lab) which has had good reviews. I know
G8LRD (David) uses one with his FT817 when out portable and works some decent ranges. I cannot remember what antenna he uses.
The image is from the SG Labs website. I hope they don't mind me linking to it.
As you can see, this is small and light enough to be mounted on a portable mast close to a 23cm antenna to minimise cable losses.
As I could not find a price for this transverter on their website, I dropped them an email. I got a reply very quickly: 156 euros plus 8 euros economy shipping to the UK. They accept PayPal. Not bad for a 2W, sensitive, transverter. This is for V2.3 which also accepts an external 10MHz reference.
See
http://www.sg-lab.com/TR1300/tr1300.html