Amazon has lots of options for couch legs.

eBay has mid century 'taper legs' you can order

Have you considered shorter back legs? They won't be as noticeable and give you more options. Also, you might be able to get a woodworker to make you the exact legs you want/need so all 4 match and are the perfect height. It shouldn't be terribly expensive.

Move the sofa, or ruin the sofa legs and the sofa proportion. Screwed in sofa legs are inherently not very stable. Th longer the leg............the more unstable.

Thanks everyone. The sofa is fully supported by the concrete ledge it is on. It overhangs a few inches in the front and my husband is concerned someone will tip it up (very unlikely) so the longer legs are to appease him. As for the design aspect that will have to wait til we complete the total rewire, re-plumb and new roof.

Castors?

H-74 1" Square Cup Caster, Light Antique · More Info

I may not be interpreting this correctly but it looks like the sofa sits up on a platform and the back legs are removed...the front ones touch the floor. So what is wrong with the way it is now?

Longer legs won't help anything and they might ruin the look of the sofa.

leelee they do not touch the floor. But the problem is solved. The guy who is doing our iron gate was here and he's going to make 2 legs for me.

You'd be better off increasing the depth of the platform......... and leaving the sofa alone. The entire concept will give nobody a comfortable seat, the sofa will "sit" too high and legs will dangle above the REAL floor below the platform, and the look of the sofa ruined as well.. Move the sofa, or add a foot to the platform depth....allowing the sofa to be the sofa you purchased with folks having a place for their FEET. The result as planned is guaranteed "Kludginess" ON ALL COUNTS : )

I think Jan is right.

There will be a pool table in front of this area so extending the platform is not an option. This sofa is temporary. It was chosen because it sits pretty low and was inexpensive. Believe it or not, it is quite comfortable.

I am having a custom piece designed to replace it. Since that is at least several months from completion, I needed something usable so my husband and I are able to use the space and entertain guests.