Wow. Mike responded to email in about 10 minutes.

"Part number TOH5L is $34.95 plus shipping.
Part number TOH5N is a conversion kit that lets you use regular 9V batteries. $47.95 (with the batteries)."

I'm thinking of just going with the TOH5L. Not because of the price, just because that's what it was designed for, and I'm guessing with my usage patterns, I'll replace the battery about once a year, if that. Any feedback on this idea is welcome (I know it doesn't make financial sense).

So, off for another bid.

Thx
Matt