Hi ollie,
To put it quite simply, we're not going to get involved with any type of valuation here on this site. Your best solution here is having a look at past sales on eBay and that will give you a pretty good idea overall.
From my personal point of view it isn't worth more than a few dollars as Model 40's are just not sought after in any way. These are not to be compared with the Model 45 in any way when discussing money. It's like comparing apples with strawberries.
Best of luck with it.
BB.
