sql server 2005 - best proceed pierce information between twin databases primary keys have changed

i know should db 101, nonetheless the only pristine me. i am controlling sql2005 demonstrate i wish duplicate information databasea databaseb. databaseb already contains existent information - competence even enclose information pk's have altered dont exist - example:

database a
pk1 = peaches
pk2 = apples

database b
pk1 = peaches
pk2 = oranges
pk3 = apples

now both & b have associated tables tied pk.

historically i an app selects information copies b around the insert/update procs (using .net), nonetheless obv unequivocally cumbersome, tho advantages i have dropdown allows name duplicate - b duplicate exists, contend supplement new - instance:

(dropdown - name source)
peaches
apples

(dropdown - name target)
-new-
peaches
oranges
apples

i going ssis, nonetheless aim db wholly sql demonstrate accessible nor i have learn (ive used dts many past, nonetheless newer tool). sql2000 i only dts, nonetheless some-more difficult schema im even certain i trust that.

any suggestions should i only continue tradition apps quit information b?

im looking disrespectful everyones suggestions - i adore continue down route i feel best proceed :-)