what kinda taper are you looking for? JIS, ISO?

I don't think shimano BB's come in 103mm.

you could get an FSA ultimax
http://aebike.com/site/page.cfm?PageID=30&SKU=CR4499
TA makes one too. kinda spendy though
http://www.peterwhitecycles.com/bottombrackets.asp
phil's is even more spendy
http://www.philwood.com/webcatolog/pg11.htm

if your looking for campy, you can get a chorus BB in a 68x102 for about $60