I hear the single IR is a dead duck and probably worthless
Frequently posted misinformation. There are many bods flying on the NS who took the SE IR(H) route.
The FAA to JAA conversion is only cheaper if you don't need additional hours to get up to scratch with ADF and reaching the standard in an aircraft in which you have only a handful of hours. Quite a few people end up spending at least the difference they hoped to save.
TT