Depending on the growth rate of your child's feet, you may well get enough use out of cruisers to justify them.
S had/s micro-feet, so we ended up using a combination of cruisers and Pedipeds (google them - they are fab, more waterproof soles than Shoo Shoos) for some time, even when S was walkign confidently as it was nigh impossible for us to find walker shoes in her size. She has experienced no ill effects from using them by the way.
Cruisers are particularly fab when the child can walk, but likes to switch to crawling just because they can - particularly when playing etc as the front is normally rubberised and doesn't scuff like a proper shoe.
Have you asked at Clarks? Not that I wouldn't expect them to try and sell you a shoe, but they might have some info that will help you decide.
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