I think the value of a watch in good working order is determined by availability, original condition of the watch and whether or not it has it's original bracelet. That being said sometimes it boils down to what the buyer looking for that particular model is willing to pay. Do you have any photos of the watch in question?
I assume you are asking about one of the variants this watch (it also comes in black and IIRC, silver):
[i]picture source: Iavolto[/i]
If so, we are not really in the habit of giving valuations. Your best bet is to check the markets. eBay and the trade forums are good prices for sources. I can tell you this much. Amongst vintage sport divers, this line is fairly popular. The one most seen is the orange, followed by the black. The silver dialed one does not often come up. I have a nagging suspicion that there might have been a blue one, but don't quote me on that. Price depends VERY HEAVILY con condition. A perfectly restored or NOS example on its original bracelet can easily command the mid $300s. However finding one is easier said than done. for some reason these tend to be the victims of ham fisted sellers looking to make a buck more often than other many sport divers. Also because of their size (they are bigger than many sport divers), I suspect that many owners treated them as real divers. Many vintage examples of this line show wear an pitting in the case back seat. Normally a decent one in restorable condition can be had for about $125 to $150. Less if condition is not the best, and more if it is good. Factor into your price the cost of a full, CORRECT, physical and mechanical restoration. if you over pay, yo could easily bump up against the market price for a fully restored example, or surpass it. so it behooves you to do your homework.
I know the watch in question very well. There are 4 dial colors: orange, silver, blue, and black. As mentioned, they are not easy to come by in good condition. Original replacement bezels are the hardest to source. Gaskets + crystals are available. The one I've acquired didn't come on an original bracelet but I put a vintage Seiko oyster on it as soon as I received it.
As already mentioned expect to pay between $100 and $150 for a reasonable piece. Our friends on eprey seem to have them
on a regular basis. I have a few in my collection ,including my fathers yellow /gold version ,a black version with NOS bezel and insert,
and a blue version. Will have to track down the silver version one day. As their is not to many nos available for this watch I would wait and
find one with a decent bezel insert that has not faded to much..................