Source for Trials No. 4 T scope bases?

[Surpmil]

The way they were removed suggests either 3rd world country or a civilian bubba, which might give some slight hope of finding the pads if you could track back to the previous owners.

If Bubba had hammered or chiseled off the pads one would expect some visible collateral damage, so my guess would be he torqued the screws until they broke, and having got them out and found the pads would not budge, "the light went on" dimly, and he realized solder was involved and so used enough heat to get the pads off over the screw stubs.

Could this effort have been connected with an attempt to fit PH "Enforcer" type bases as I think you alluded to there being some rifles so fitted in the same lot as this rifle was in?

Stock looks to be off a 3L Long Branch and from the state of the scope number on the wrist, it's been on there a long time.