Good clean ad Richard.
One thing I've thought of, but never done myself, would you offer their members a discount, but instead of 10% off to them, turn the discount into a donation to their church?
That will do a couple of things, track any jobs you get directly from that marketing to see if its worth pursuing in the future, but also show them that you are supporting/appreciate their prior business. Add into the mix that often a donation comes in the form of a tax break kick back. Not to undermine the value of a donation to a church, but it often allows you to be more generous in your offer/discount to their members. The also benefits from a higher donation.
John