i have a 350 olds i think is a 72 model motor at least thats what ive been told the casting number on the block is 395558 2 and it has 7A heads

 

That's the right block number and assuming the heads are 7A (the A is smaller than the 7) and not 7A (both are same size) they would be '72 heads. Since that block number was used for a span of years and heads can easily be swapped, the only way to be sure is to check the VIN pad on the block.