Oh, I forgot to mention. The ARF version of this kit has fiberglass cowling and wheel pants so they should be availible unless they were dropped when Lanier bought GB. Looking at the parts list here is the info:

P/N Description Price
------------------------------------------------------
6101 Fiberglass wheel pant - left $22.00
6102 Fiberglass wheel pant - right $22.00
6103 Fiberglass cowl $50.00

Quite steep in price but they are pre-painted in the ARF version with the stripes applied so that might be the case in the replacement parts and why the price is so high.