Speaker spike feet?


I recently acquired a nice older hifi system with Aerial Acoustics 7B tower speakers.I am not an audiophile. The speakers have heavy iron bases on them but there are no feet of any sort on these bases. I emailed the owner/designer at Aerial and he sent me a schematic of the bases which show that they originally had spike feet. He said he could provide the spikes at minimal cost. I was afraid to ask what minimal meant since I seem to remember that these bases cost $400 when new. (I'm still getting accustomed to what things cost in the audiophile world.)

I am wondering if I really need the spikes. These speakers sit on a carpeted floor with hardwood on typical joist construction floor. They sound quite good to me but if spikes would help in any way and I can get them cheap then I will do so.

I'll ask Aerial how much theirs cost but I'm pretty sure that stainless steel tripod (for photography) spikes will fit the 3/8-16 threads in these bases. The cost would be about $40 for those. Maybe the actual Aerial ones wouldn't cost any more but they are longer and look very sharp which makes me wonder about floor/carpet damage since these speakers weigh around 110 pounds each.
n80
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Addyson et al......don't use pennies.....the spikes easily make their way through the metal..   
@stringreen 

"  the spikes easily make their way through the metal..   "

it would take a while to do so.....and I am sure that pennies could easily be replaced and it wouldnt cost much......
OP,
I know you are looking for cheaper options. But if the original owner is offering you the original spikes for $400, ignore it and go for GAIA feet instead.
If you are looking for reasonable prices and good quality, try www.oregondv.com.