Hi:
This is almost certainly not a 54, do you have the serial number? The 20" Speedster does not show up until 59. Color appears to be Radiant Green. Is the rear axle a Mark IV? Seat looks like the correct type for 60 and up. Here is the page from the 60 catalog:
http://www.trfindley.com/flschwinn_1951_1960/1960_12.html
Value wise maybe someone else will chime in but these small bikes just don't seem to have much. If I saw it for sale I would have a hard time paying $50 for it and would like to get it for $35. But that is just my opinion.