Wheels are terrible on anything but flat, even terrain. Rubble, stairs, a rope bridge, a steep slope, etc- adventure sites often involve terrain that makes a wheel chair seem pretty useless.Out of curiosity - why? Why can't it be a wheelchair? Why would magical spiderlegs be better than magical wheels?
Sure, such a cleric (or wizard, or whatever) could exist, but it doesn't seem like the kind of character who would casually go into a dungeon.I'd ask those that are uncomfortable with this mini to flip the script and see if they can be creative enough to find a place for an NPC cleric like this in their setting. Why would a cleric not heal their own legs? How would a cleric in a wheelchair operate? How would you make it fit into your setting.
GoT didn't ever show us any magical healing outside of resurrection that I can recall.As a reminder, we saw Bran in a wheelchair in GoT, right? There were priests in that setting that raised the dead - but Bran was in a wheelchair. And he was a pretty powerful magical being, in the end, and stayed in his chair.