I don't think I can buy US govt bonds directly.
But 10 year bond yields are at 3.16% - to me a very attractive rate for the long term.
Is there a way for me to enjoy the 3.16% 10 year yield?
Well hey, there's a couple of things going on here. Let's talk about foreign government bonds.
Firstly, don't forget, that 3.16% comes with currency risk! A 10-year Singapore government bond yields about 2.6%, so you're only earning an extra 0.66% per year; if USDSGD drops to 1.3340 (where it was as recently as June!), that wipes out
five years of your excess interest.
Secondly, is there a reason you're looking at the 10s in particular? I tend to think the short end's a better bet at the moment: the curve's relatively flat despite yesterday's enthusiastic bear-steepening, and short-end yields are relatively high, so they've got a lot of insulation against adverse price moves. If you're absolutely hellbent on doing the trade, I reckon you're better off in the 3-5yr sector (and, money where my mouth is, that's about where my bond portfolio duration is at the moment).
So I don't think US government bonds are a good idea for you at the moment, and I don't think the 10s are a particularly great point on the curve. But if you're hellbent on doing this, there are ways:
1) You can open a Schwab account, and buy them there. Don't forget that you'll pay about 0.5% each way in FX spread, which will wipe out two years of the excess interest.
2) If you've got a big lump to do (over 100k), you can buy them on Interactive Brokers, and get a much tighter FX spread; or,
3) You can buy a US government bond ETF, which should (I'll defer to BBCW here) not have any adverse dividend tax treatment, especially if you buy a UK listing. IEF (US listing) or IBTM (UK listing) have the 7-10 year part of the curve that you're after. BBCW: what's your take on whether IEF (US-listed US govvy bond ETF) would have any weird div tax treatment?
So the upshot is: yes, there are ways to buy US government bonds, either directly or through ETFs, but I think it's a pretty bad idea at this point.