Monoprice has cords in one, two, three, six and ten foot lengths and they cost dollars.
Audio advisor has some inexpensive cords from Pangea that average about 99.00 . The company than made the iron Lung Jellyfish cables is no longer in existence since the owner Paul Grzybek passed away 3 years ago this month.
Been there... Costs as much but audio gear won't pee on your rug.....
I don't use an expensive power cord, but if 120vAC is coming directly out of your receptacle, I would think if there is nothing between the the amp and the 120vAC coming in, you are probably not going too hear a big difference (if any) with the power cord. I believe if you have some type of line enhancer/filter, between the amp and the receptacle, maybe then the power cord can perform too it potential by receiving an enhanced/filtered/cleaner signal. I am only saying what I believe would make sense too me, I'm not saying that you will not hear a difference, I have no experience with expensive power cords, and I also use a line enhancer for all of my components with no noise issue what so ever… these are just my thoughts. I use a 14 gauge Monoprice power cord, going through a AC line enhancer with no noise issues or interference what so ever.
I can't recommend you one due to the fact that mine is close to 25yrs old, and I'm sure there are more technically advanced ones out there, but I've never felt the need too replace mine because it also functions as a 30sec power on/off delay/surge protector/AC line enhancer. (I purchased new) and it works as well now as it did from day one, and its got countless hrs on it. I'll give you the info on it if you are interested in it, these are for sale on eBay; Adcom ACE-515 Line Enhancer. The last time I looked they were about $50.00-$100.00U.S on eBay. I know its old but...
I'm sure someone else has one from this day and age they can recommend if your not interested.
Geez, I just saw the price of these things!
He could buy a whole new headphone rig with these prices. Lol!!!
Came across this while browsing ebay :
Why is someone bidding $ 288 for tubes with broken glass ?
The used units are much more affordable.