If you kit works well for you, why change cameras? If you want a shutter, there are plenty of 8x10 lens out there that won't break the bank. You can even have your lens mounted in front of a shutter but the machining required might approach the cost of a second lens. Packard lenses work, but I fret over drilling that extra hole in a good lensboard.
IMHO get a second lens in a shutter (after all, you've got a legit excuse!)