Thanks for the link, but I too have looked many times for a tachikoma in the right (sort of) size, and found many of the ones you show here, but until now I had no idea just how big/small they were and whether they'd fit or not - thanks for the photo!
Which is the one in between the metallic one and the Uchikoma? Because to my eye that looks the best fit. Or perhaps one of the three on the row behind it.
Cheers!
Duncan