$150 is great but there are a few things to keep in mind..."all matching" doesn't mean anything. It can be force matched (######X out old numbers). It can be a completely different stock which has the serial number manually etched. On top of that, is it a refurb? There are many different things to check for this from the stock, to the peen in the bayonet area to the rectangle with diagonal line to BBQ paint, etc. Are you sure it's all matching - some people mention all the major things but neglect to mention the smaller items that should match via natural match, electropencil, etc.
Maybe you got a good deal. Even if it is a shooter, $150 is great. But does it work? Is the gas tube and piston all seized? Is there a bunch of rust on the metal once it's removed from the stock? Lots of things to check but yes, I would say given the average condition, $150 is a good deal for a 52 Tula. But if you are planning to flip it for $900, you better know exactly how to justify that $900. Because the discriminating buyer will for sure be checking certain things.