Which stock pattern? - I have seen four differing styles of R/B stock on the 300 so far!
This is my FWB300 R/B picked up in a trade a while back: http://www.airrifle.co.za/picture.ph...ictureid=15912 http://www.airrifle.co.za/picture.ph...ictureid=15911
It needed a service, the piston buffer was on its way out and the springs were a bit tired, also stripped the varnish from the stock and oiled it as it was scratched and just looking scruffy. Now looks nice and shoots sweetly yielding around 600fps with JSB Exact, about 630 with Finale Match.
As to finding an R/T scope - from all accounts they are not cheap (especially if bought new), but can occasionally be found s/h.