OP, what are you calling legit?
What time period are you looking for?
There are a lot of "legit" Mosin Nagant 91/30 rifles out there, mounted with PU or PE scopes.
They will have all sorts of markings on them, depending on which nation built them or used them last.
All of the ex USSR nations, China, Korea, Finland, South East Asia, Middle East, Cuba and any nation that had Russian aid or influence fielded these rifles.
Many rifles were torn down and returned to service/storage as regular infantry rifles. Many others were fully restored, sometimes with force-matched parts.
Some are rifles that were put together from parts, without any refurbishment. All of the parts are correct, but they can often be a mix of new old stock and been-there-done-that parts, with no refurbishment.
None of them are for sale but I have one with a PE scope that was refurbed too as new condition, along with a PU model in the same condition.
The other sniper M91/30, which I have, has seen extensive field use, has had the scope and base replaced with a new one, sometime in the 1950s. It's got zero finish left above the wood line, with a lovely NOS scope/base, the bore is 95+% and it shoots ammo it likes better than I can hold.
I like Mosins, I also like Mausers, Lee Enfields, etc.