A few years back I remember reading an article about a rod shop modifying the 4-53 blower for use on Ford flathead V8s. You might try a search on one of the "traditional" rod forums along this path.

You could take a look at the small B&M blowers to see if there's a chance they were based on the GMC 53 series and if the snout could be adapted. I've never been up close to a B&M, so it's just a swag.

You also should check to see if high speed sealed bearings are available for that blower. The stock blower was not intended to produce boost, just scavenge the cylinder during the exhaust cycle and refil to normal atmospheric pressure.

Cheers, Mark