Replacement parts- MTH Premier NYC 4-8-4 Niagara Steam Engine

[rio grande]

I want to repolace the lower boiler trim (add on piping-right side if you are facing the front of the engine) for MTH's Premier steam engine #20-3047-1, cab# 6025. The piece or pieces seem to screw on and run almost the entire length of the boiler. I have already contacted MTH parts department and was told I would have to wait untill MTH remakes this engine. Any ideas?

Thanks!

Al