Another option for SW Thunderwolf cavalry - a miniature from Russia available (sometimes) through eBay for 12 USD (plus s&h). While the painting style of display model is rather unfortunate, the mini itself is very interesting.
I think, this model is better then original Fangir from GW Canis Wolfborn set, but still not enough dynamic. If this would be set of three T-wolves, with second one charging and third one maybe even jumping, I would be very content. Easy to say, I know... but maybe possible.