Here it is...Mothra in the box!
And to answer the earlier question, the Godzilla's have rods that the feet move up and down over as the figure walks, helping to give the illusion that the feet are actually coming off the ground as he takes a step. The tail has a small "caster" where it touches the ground, making turns and whatnot easier.
As to availability, the Godzilla's used to show up on E-Bay quite often and usually(at least the one's I tracked)went for around $500, depending on condition, but now they seem to be showing up less and less...so my advice is, if you've got the cash and run across one, don't hesitate to buy it.
The Mothra figure would also show up occasionally, usually going for around $600, but I haven't seen one listed for quite awhile now.