RE: FS110a how to upgrade to pump version
To convert the non-pumped engine to the pumped version, you'll need:
OSMG2511 44982000 CARB 61P FS110A-P US$144.99
OSMG4157 44907030 COVER PLATE FS110A-P US$23.99
OSMG6501 44969430 INT MANIFOLD FS110A-P US$25.99
OSMG2200 72508100 PUMP PD-08 FS200S-P US$89.99
These parts can be ordered through any hobby retailer who sells O.S. Max engines and accessories.