Hello Jenny
If you have access to the British Library, you can get a copy of the baptismal records from there.
If you actually ask the British Library to supply a copy, it will be a transcription, not a copy of the record they have,.

If you don't have access to the British Library , you can get a copy from Family Search. Details in the Fibiwiki page link previously provided. It will be cheaper, and it will be a copy of the British Library record, not a transcription.

Cheers
Maureen