The base looks like a short weaver rail. Not sure way knowing is needed but pull the scope and see if it looks like a weaver. Not a big deal to pull it . I see the barrels vented?? Not a bid deal to put the open sites back on it ether. If I was buying it I would want the base off just to see how well the frame is .
I have pulled a old mount off a dan wesson revolver a couple times over 20 years just to check, clean and lube and reinstall and found my practical zero did not change enough to matter for hunting.