I just bought an old Ruger M77 in 458WM.The one with rear safety tang
It is a very nice gun but I want to replace the stock with a synthetic stock.
Who is making/selling stocks for these old Rugers ?
I have been looking all over and I only find stock for the M77 MK2.

Ramline used to make a plastic stock for the 77. The barrel channel will need to be opened as it is designed for up to .338WM diameter. They sold for $39.99 new. Look around and you can probably find a used one. They hold up well, I've had one on a .338WM for about 25 years.

McMillan is making one for the tang safety now.
https://www.mcmillanusa.com/mc...ting-stocks-ruger-r/

Mark Bansner. I have a couple and they are nice though are not drop ins.

I would give MPI a call
Thet build for ;ots of rifles...