I used 7/8" bushings from a historic to replace the 1/2" ones in my 55 Jr., I think it was a better choice then the long 1" vintage length. No drilling involved, just press in. To explain... I put 1" bushings in a R8, so I had the 7/8" laying around.
If you cannot source something in the U.K. then Mojoaxe is your best bet here in the states. They make great stuff (a wrap tailpiece with a compensation ridge cast in) and Dan is a pleasure to do business with.
This - from the Craigslist ad
1956 Les Paul Jr in very good condition, has original dog ear P 90, pots, bumble bee cap, pickguard, nut, finish.
Tuners are recent vintage Kluson replacements and tailpiecec is recent Mojoaxe nickel plated alum, compensated for better intonation.
Nice C shape...