I should think that sourcing these wheels from a higher detail source would pay dividends. They can always follow the lead of Tamiya ( plastic kit manufacturer ) who are selling the weapons load out for their newly tooled F-14A Tomcat as a seperate item to ( ostensibly) keep the kit price down.
Options may be the way to go .....if your production runs do not justify making your own, perhaps sub-contracting may be an answer. Of course, all of this will impact the retail price.....but if they can have this product RETAIL at $70 ( American Excellence price ).....tells me that a higher grade set of wheels do not need to add that much more and still keep the MSRP quite low.....beats the heck out of paying $200+ !
And, worse comes to worse, we, as collectors can opt for that upgrade on a 1:1 basis.......I'm guessing about $40-50 at retail, for some truly impressive rims.