Good sugar free lemon meringue pie recipe?

My mother's birthday is tomorrow, and she wanted a sugar free lemon meringue pie since she is a diabetic. However, I couldn't really find any to buy around at the local markets since they are all with sugar. What is a good recipe to follow or sites to check that I can make one myself? Also, could I just make a lemon meringue pie but substitute sugar with splenda? Thanks!