Jim,

According to the plans, the Royal B-25 is about 10" narrower and 9" shorter than the H9, so I'd think it would be difficult to make the H9 canopies work without lots of cutting.

I was over on eBay last week looking for Mitchell stuff, and there was somebody offering new canopies for the Royal B-25. Just checked, they weren't there today; but you might find them by looking from time to time.

One other path you might explore: a couple of years ago, there was a gentleman with the screen name "Dionysusbacchus" that offered Royal B-25 canopies. He decided to stop posting, but he'd also done a detailed P-61 cockpit for the VQ Black Widow. VQ offerd this as a "Zollner Cockpit" from Zollner Models; that website pointed me to an Ebay seller named Zollner-1 that might be the same guy.

Good luck,

Fred