Bob -
A couple of suggestions for your SB-200. Now is the time to clean and "refresh" your SB-200 (e.g. tubes, needed changes (didoe protection of multi-meter, etc.)
I highly recommend that you look at Bob Norgaard's highly regarded SB-200 Rebuild Notes (with photos of updates and protection additions).
http://home.gci.net/~rnorgard/ampnotes.htmlHe covers about very possible update or change that should be considered. He did have a "kit of parts" avaialble for SB-200 owners - at one time.
The steps that I would definitely recommend are:
Diode Protection for R12 (meter)
New Value for C10 (.0025 uF, 10 kV) - better 80 meter operation
Extra Meter Lamp Bypassing (2 - .02 uF disk capacitors)
Filament voltage measurement to 572-B tubes (to prevent early failure of tubes)
http://home.gci.net/~rnorgard/images/SB200-11.jpgHV Filter Capacitors changout
Harbach Electronics (catching up on summer orders)
http://www.harbachelectronics.com/ Rick Measures' web site
http://www.somis.org/ w9gb