I'm reluctant to advise this ( it is not a nutritional meal long term ) but have you tried day old chicks?
In a smaller snake you usually have to break it up into either legs or heads ( neither of which is a great meal nutritionally ) but nearly all of mine love the occasional chick when offered as a bit of variety.
I have not. There are not many active poultry around me at the moment, so finding them could be difficult, but I'll put out feelers.
Thank you for this suggestion. I'll try one, but will not be offering them weekly for sure.