There are two S-62s currently airworthy on the entire planet, one at Gearldtown Au, the other is in Alaska. There is also an HH-52 in Alaska. No an HH-52 cannot be converted to an S-62. They are essentially the same aircraft, different hydraulic system, electrical system, and, some of the dynamic parts are not interchangeable. The HH-52 was originally designated as the S-62C before the Coast Guard bought it, the Faa will only allow it to be run in the restricted catagorey. Parts are not just difficult to find they are darn near impossible. Nobody overhauls components for them anymore.