The common claw foot tub was and is a 60" by 30" tub with four holes. Two for the faucet and two for the waste and overflow. The faucet would be mounted to the foot of the tub just above the overflow plate.
I didn't say the standard tub because "Standard" was a plumbing fixture manufacturer and I was trying to avoid confusion on that point. "Standard", like other large fixture manufacturers made common style tubs as well as grander tubs. Grander bathtubs were often both larger and more ornate. More ornate refers to the style of supply valves and drains that served the tubs, they were an assembly that incorporated the supply valves and drain into a single assembly that is known as either a "Standing Waste", or a "Tower Drain". These assemblies were affixed to the tub in a number of fashions. One way to mount them was to have an extra wide tub rim with holes in it that the upper parts of the standing waste would pass through. Thus the hot, cold, and drain controls would rest above the curvature of the tub rim. These tub are known as "Through the rim" tubs.
As for the size of the larger tubs there is an euphemism for larger vintage bathtubs, they were known as a "Taft tub". This refers to William Howard Taft, the 27th President of the United States who was a very large person and enjoyed an extra large tub.
I have such a tub available for sale with a fully restored standing waste kit ready to install. It is a 1911 "Standard" Through the rim Taft Tub. It measures 66" long and 34" wide.
I have written a blog post about it that can be found on this website's attached blog and dated,
Thursday, November 2, 2017
This tub's standing waste has been plated in polished nickel. The valves are completely restored to full function and quarter turn ceramic disc service valves have been added to the risers.
The outside of the tub was plastered smooth when it was first set as the feet are still set with the square iron nails of the period.
The base of the feet are full balls with the forth claw on the back.
This tub is primed and ready for top coats of the paint color of your choosing.
There are no chips in the porcelain but the surface is eroded and there are some stains. I would expect the interior to be re-coated but that is not an imperative.
This tub is priced realistically at $10,000. It can be delivered local to the Portland Oregon area in which case I would be available to install the fixture.