ideas-oversized Sousaphone gig bag

[vanpemr]

I have a restored 1928 York 786 sousaphone, 26" bell. Lee Stofer tuned it up and recreated the upper leadpipe, and it plays incredibly well.

Problem: it doesn't fit quite right in the available (non-original) case, specifically the lower leadpipe riser is too tall. I have to use a PVC cap to protect the leadpipe assembly when in transit. Plus, of course, like all wood cases it's awkward.

So I tried a ProTech gig bag that looked as if the bag would fit according to their dimensions. It doesn't; the bell alone is too tall and the bag won't zip closed around the wrap, and of course that lower leadpipe assembly would be under way too much pressure.

So, I need a different bag that's bigger internally. Anyone have a recommendation of an oversize bag?

Thank you!