Rim locks tend to be fitted to bikes that run lower pressures (typically 15psi or less) such as dirt bikes in competition - the aim being to stop the tyre moving/spinning on the rim under power, and potentially ripping the valve out of the tube.
Most off-road orientated rims will hold a tyre just fine at 18-20 or more psi, it's only under extreme acceleration at lower pressures that a tyre might slip.
For general travel on or off-road, you are probably going to be running similar pressures (or higher) unless you are aring the tyres down for soft sand for example.
I had rim locks in both my Honda XR400 and 650Rs, but after fitting mousses for a rally earlier this year, when it came to refitting tyres and tubes, I left the rim locks out for my trip around Europe and Morocco, and it hasn't made the slightest bit of difference.
If you do decide you need them, one thing you should consider is that rim locks do alter the balance of the wheel, which is why some people fit two (opposite each other). It is a case of simply drilling a hole through the centre line of the rim for the bolt to go though. They do make things a little more tricky when refitting a tyre, but not significantly.
Personally for overland/adventure riding, I'd not bother unless you'll be doing a lot of soft sand work - just fit some decent heavy duty tubes and the tyres you suggest are a good choice for on/off road riding - if your rim already holds a 130 width rear, then the 130 TKC would be fine. (for your info with a 130/80R17 the 130 refers to the width in mm, the 80 is the % ratio of sidewall depth of the tyre compared to the width, the R is speed rating (or sometimes can also indicate Radial belts) and the 17 is the wheel rim diameter in inches).