Recommend good isolation

Cheap, Chemical rubber bottle stoppers. Size 10 cost about $1 up to $1.50
I got mine (I have about 4 dozen) at American Science and surplus.
Everything I own sits on them. Even doubled up, with an 8 on top of a ten set, for my SP-15 pre.

When thinking 'isolation' more then the 'pad' needs to be addressed. One of the most overlooked issues with isolation is the amount of acoustic engery that is flying around in a typical listening room. So, think of ways to 'acoustical' shield all your equipment. Few do this and miss an opportunity to bring their listening experience to a new level. The most important component that needs this 'shielding' is the turntabel/arm/cartridge. Often putting it in an adjcent space works best.

Not cheap, but not horrible expensive : Herbie's products. 90-day guarantee, money back. Always worked for me, sometimes *really really* well, brought out the best in my best gear. Email Steve Herbelin and ask for a suggestion if you like, he's been right on the money in my case.