Hi Jeremy,
From what you are saying it certainly sounds like the valves are not searing correctly as with worn rings if you add oil it will instantly up the compression for a short while. Many of these engines will survive quite well with refaced vales and seats done and then a new set of rings. Apart from that there's not a real lot else you can do, unless you've got a totally flogged conrod which I'm sure will be fine.
As far as decals are concerned they are all available via one of our members who is the main seller of decals on eBay. If you can't see what you require you'll only have to write to him and he'll re-list the ones you want as he's been known to let listings slide off the system.
Cheers,
BB.
