Lee Collet Die for 7.7X58 Arisaka

[TCLouis]

My Lee and RCBS dies both work the base of my 7.7X58 brass far too much every reloading so I want to neck size til they must be full length resized.
Someone posted here that they are using 303 Brit Collet dies, but I only fined a full set of dies for that.
Looking at Mid South's catalog they list 30-06 Collet Die only and I'ma thinkin all I would have to do is make a ring to drop over 7.7 brass that would activate the collet mechanism and make up for the difference in length to the neck between 06 at 63 mm and 7.7 at 58.
The reason the using the 30-06 collet die is so tempting is that I shoot the same boolits out of the 7.7 as I do my 30cals.
OR if someone has the 303 they don't use I could solicit for it in classifieds.

[curator]

Why not contact Lee Precision directly? I have bought single dies from them in the past. The advantage of using the .303 British collet die over the one for .30-06 is that both .303 & 7.7 cartridges are the same length (58 mm) and shoot the same bullet diameter (.311-.312)