I really don't think any Alexander owners would give him up for Tiki, but that's not the main pointof this post. (Go ahead though, it never hurts to try to see if the owner would bite.)
I think you can get Boston for a whole lot less than Chambers. You should be able to get him for the worst 1-2 players on your roster who are barely more than waiver wire fodder.
I think it really is the time to buy low on Boston, but just make sure it's very low. This window of ultra-low value will certainly last for the next 8 days, and it might be even easier to get him if the Boston owner loses this week and really feels the pain.
... in my opinion, of course - but that should always go without saying.
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