If you have enough of it I would try this before rushing out and having it stabilized.
(Because I use CA on my glue ups I cannot have my blanks commercially stabilized but I do successfully turn "difficult pieces")
If you have been able to drill it, you should be able to turn it.
IF you have drilled it for the tube successfully try thin CA in the hole to stabilize it from the inside out.Let it set.
Id say at least 10 minutes to be safe.Give the Hole a shot of accelerant.
Run the same drill bit inside the hole to clean out the excess CA.
Glue the tube in as usual.
To be safe I would carefully seal the ends of the blank with thin CA before milling.( try not to let the CA get in the tube)
Ease the corners of the blank to reduce the shock of roughing. You can do this with a sander or with a jig for the band saw or table saw.
MAke sure your tools are sharp and use plenty of CA to stabilize while you go.
Or you can mail it out, wait for it to come back, pay the postage and stabiliazing fee.
<b>Or you can turn it today.</b>[
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