How much something is "worth" is only equal to how much someone is willing to pay for it. In other words, if someone is only willing to pay $5 for it, then wow...that's what it's worth; $5. If you're worried about getting "ripped off", then you may wish to wait on the televised auction thing and get the item(s) in question properly appraised, along with COA's (Certificate Of Authenticity). Posting such items on Ebay will also give you a better than fair approximation of what your item(s) is worth as you can tell from the bids how popular it is and how much someone's willing to pay.
At the risk of being blunt here, me thinks you're just looking for a quick fix on the internet and in all fairness, I doubt you're going to find it. In theory there's just too many things to consider regarding the resale value of stuff like memorabilia, I.e. how rare is it? Is it rare for a reason (such as no one was interested to begin with)? How popular was/is it? Remember - just because something is "rare" doesn't always mean it's "desirable", let alone that some idiot's gonna fork out cash for it. Condition...how well was it stored? How well has it held up in storage? Is it damaged in ANY way? Can it be verified? Is there a signature or handwriting that an appraiser can look at and compare to specific examples? It's one thing to say "my mom was given"...it's another thing entirely to prove it! Can you even prove you have the legal right to sell these artifacts? Verification is a BIG thing when it comes to items such as this....after all, anyone today can fire off such things with an inkjet printer and just make them look "old". Likewise, I see pictures/images there...are you SURE you have the right to sell them? These days copyright ownership is ALWAYS a very big issue...and I can promise you that the lawyer's fees will FAR exceed any profit you might make on the sale.
In other words, there's a very good reason why appraisers charge for their services and are usually reluctant to provide quotes somewhere such as an online forum.
So that all said, if you truly don't want anyone to get ripped off (including yourself), take the time and do the PROPER homework, seek out the services of an experience appraiser, get your item verified/certified and KNOW what your item is worth BEFORE you try and sell it. If you're just doing this to get you or your mum on Antique's Roadshow, you're doing it for the WRONG REASON and you'll likely get screwed.
