Matching transactions between datasets

Hi all.

I need to match transactions from two different data sets. Specifically, for any given transaction in dataset B, on the same sheet (so I can go entry by entry without switching back and forth), show a subset of possible matching transactions from dataset A where I can select the match and generate a link between the two transactions.

Is there a way to do this using a pivot table or other Excel data function?

More details:

In dataset A, I have:
- Claim Number
- Date of Service
- Provider
- Patient
- Amount billed
- Other stuff

In dataset B, I have:
- Transaction ID (not the same as claim number)
- Date of Service (may not be exactly the same date as in A)
- Provider
- Patient (may or may not have this information)
- Amount paid (may or may not be the same as Amount Billed)
- Other stuff

In dataset B, I want to enter the Claim Number for the corresponding transaction from dataset A.

I want to click an entry in B and display a subset of possible matching entries from A. For most entries, I should be able to select a few candidate transactions from A based on provider, date, patient and amount. Many entries may have only one candidate if all entries match nicely. However, if I'm missing some entries or the date or values don't match, there may be several candidates to choose from.

Any help would be appreciated.
-Quercus