Late Uncles Inland M1 Carbine. Still teaching my boys.

[W5USMC]

If the carbine shoots and functions as it should then leave the springs alone.
As far as the upgrades Singer B mentioned. 1st off your stock has a Rock Island Arsenal rebuild stamp which indicates a post war rebuild. It has an Underwood barrel, Inland used Inland barrels. It originally would have had a push safety and a type 2 barrel band, you have a flip safety and a type 3 barrel band.
I am assuming that your serial is 5171??? and not 5171??.