We do have a few surplus suppliers listed within our directory, one you haven't mentioned there is viatrading. I can't really recommend any personally, but I would suggest that they are one to take a close look at.
The problem with surplus is that many buyers have crazy high expectations, they treat surplus suppliers like wholesalers, which of course they aren't. Buying surplus for the inexperienced can be a mine field, plenty of ways for things to go pear shaped for buyers, so you need a dealer who will work with you and help you understand the market and the stock they sell.
One tip I would give when dealing in this market, be careful what you call junk and then dispose of. A broken vacuum cleaner may still have usable parts to sell, a broken stereo may still appeal to a buyer that knows how to repair it, an incomplete knife block set still has some knives you can see and even a block on its own and so on.
The point I am trying to make is that many don't see the potential if products they deem rubbish, the real trick to successful trading in this market is squeezing every last little bit of profit out of it and even when you don't think you can sell it, even for parts, keep it because you never know when you'll get another in another load that you may be able to make a complete unit out of and then sell.
A really good dealer in this market throws very little away and understands that it isn't always a quick way to make money, but most who do it right do make money from it in the long run.
Talk with the supplier, discuss the damage rate you can expect in your load of choice and so on. Keep your expectations in check and dabble a little would be my best advice. Key thing to remember with any investment, if you can't afford to lose it, then don't spend it to start with!