Putting a value on these is difficult for several reasons. First it's my experience that these are not exactly what I would call collectible, I've never been asked about buying one and I sell a lot of collectible gas pumps.
However that's not to say that someone might find them interesting to set on the shelf.
From a salvage standpoint I don't see many parts that could be used on a clock face pump.
From a actual commercial use of these, I have no idea if there is a market for them.
If your looking to sell and have no idea of value I'd stick them on eBay at a low starting price and see what happens, to me that would indicate if they have value.
Tom.