Not sure what "break the bank" means to you, but I use a Musical Surroundings Nova Phonomena with my 103r. It has DIP switches for Capacitance, Resistance, and Gain that work well with the low output 103r. The Nova which runs on rechargeable batteries costs $1,000 new, can be found used in the $600 range.
I haven't heard other preamps with the 103r so I can't comment on comparisons.
I haven't heard other preamps with the 103r so I can't comment on comparisons.