Howdy Phil,
It's a 2 HP Silver Briggs engine that was built on the 7th of January 1970, that's assuming the air / starter cowl being the original fitment to the block. This engine was used on the 14 inch Model 45 from day one of production of the 45's until they swapped over to Kirby's across the full range and then went to full Briggs across the range.
Cheers,
BB.