Debbie
Thank you for your efforts! I've have found the Drew family in the Marcham parish records, as you say, they are a little early for 'my' Richard Drewe. However, looking on the IGI, I have now found a batch covering just a few later years, and there is a Richard Drew born Marcham 1813, so it could be him, although the date is a little early.
Yes, I'm vey interested in the St Helen's births, I presume this is St Helen's Abingdon? I looked at the PRs (from Oxfordshire Family History Society) and again they finish earlier than the dates that I'm likely to need. Is there an online source of later St Helen's records or do you have another source?
KN