Stu:
As Mike N. is getting at, new sand is one thing, but there may be other matters directly related that should also be looked at before dumping a lot of money with new sand. I'd hate to see your club throw money at something that may in fact have other fundamental issues that should be corrected first.
At a minimum, the drainage systems in the bunkers should be checked to make sure they are performing properly. This of course would come after consideration is given to the design, placement, arrangement, etc., of the bunkers first and whether or not improvements in the form of restoration, renovation, preservation and so on, should be weighed. Assuming for moment that the bunkers are all just right/perfect, doubtful, but then I don't know your club, then you need also to take in account the other costs such as sand removal and drainage cleanout/potential redo? that Mike N. is referring to.
Depth of sand is largely a subjective/playability issue as well as a maintenance one, but I have rarely found the need to go deeper than 5" and if the construction technique is good and the underlying soils not too problematic with respect to stone migration, etc., then filling to 5" and compacting to 4" works very well and the costs savings can be substantial.
Now comes the sands' performance which in this area too many opinions will leak in and throw off the decision making process in many directions. As you know, many of the new courses are using more and more indigenous sands from the site and not getting too hung up on performance...it is what it is, play it as it lies
There are those private clubs, many still, that insist on great performance and the bunker really not being a hazard (unfortunately!) and so your decision and research must take this into consideration. I will say when this is the case, the cost of the raw sand will be expensive
You have places to search out options and one is the USGA site...look under construction and find "How to select the best sand for your bunkers" It is a good article and it tells a lot about the performance of various sands.
Now comes the sand itself. Here, there are many choices and one of the better suppliers just happens to be in your neighborhood. HUTCHESON SAND & MIXES in Huntsville Ontario, IM me and I will give you the details and a contact name. There are many others and I can give them to you as well. Cost will be reflective of the performance quality and the color, but the better performing processed sand of lighter color have been running between $43- $58 per ton. The conversion ranges around 1.3 to 1.5 tons per cubic yard so you can do the math.
Be prepared for high costs. I know sand in the south is normally MUCH cheaper than here in the north. I am in Lockport, NY not too far from you. It also comes down to trucking with gas prices so HIGH!
Actual costs per bunker comes down to square footage. So a 1,000 SF bunker at a 4" compacted depth for sand alone would be, 1000x.33/27 = 12.2 CY or approx. 17 TON, so if raw cost is $45/TON then you have +- $800 just for sand.
Sorry for the long explanation, but there is more to consider than just sand costs and the variables can cause the costs to normally float up, but rarely down.