If you have the drum sandblasted all you'd need to do is a seasoning burn. The drum is also ready for paint after a wipedown and tack rag. Not so with burning. A lot of cleaning remains.
I hear ya on the $$. Commercial and industrial painters also do sandblasting for water towers, bridges etc. Auto body shops are an option. If you can locate some of those, a phone call to them might give you a lead to the right place. For reference, mine cost me a $50 bill for a complete sandblast inside and out.