Couple of RC8 swingarms on ebay ATM:

http://www.ebay.co.uk/itm/KTM-RC8-SWING ... 4ab5eee973

Do you recon they would fit as a staright bolt on? Could allow 190 rear, certainly stiffer but maybe would change geomatary too much?

nope, they would require a lot of work to get them on - you should know this dude, you've been around long enough!

i always wanted to put the pc8 exhaust system on the duke but that looks like too much work as well....