Yeah, that sure sounds dodgy, him not giving you a straight answer about the springs. And there's the possibility the springs that were removed may have been fine- after breaking in the cam w/lighter springs. You should have gotten the original springs back anyway- I suppose he kept them to sell to the next guy.
You can get the necessary tools to measure with for not much money. Eric mentioned cheap calipers and just a caliper will do most if not all of the measuring you need to do considering you don't need 0.00001" accuracy. Even splurging for a snap gauge set isn't a lot of money, considering you don't need Starrett-quality tools to do what you need to do, although good tools are a good investment if this will be something you are going to be doing more of.
A valve spring compressor would be the biggest investment, you might check w/the parts stores to see if they have a loaner.