As part of my audio system during ceremonies I've been using an SM58 on a mic stand in front of one of the church speaker for backup purposes. However recently I've been encountering churches were the speakers are placed really high and the mic becomes too far from the speaker to pick up decent sound.

I've been thinking of looking for a small, portable lightstand since their normal height would already be good enough for most venues. Is anyone here using a similar system and/or can recommend an adequate stand?

Like this?

Altman Telescopic Stand - 5-9' 524-18 B&H Photo Video

reaches 3 meters.

That seems like a good alternative, although I was more looking at 3-legged stands since they would small in terms of diameter once folded (I'm trying to keep everything as slim as possible especially now that I'm using the A7s!)

It's possible to build a frankenmicstand from the parts of two or more mic stands. (My ingenious second shooter, Stefan, thought of this, and many other things.) You know how most mic stands are three metal pieces plus legs? A base, then a metal tube that fits inside that to extend it, then an arm whose angle is adjustable? Well, you can, for instance, take the top two bits of one mic stand and add them to the bottom two bits of another, etc.

That plus a shotgun microphone, rather than a dynamic mic, will get you to most soundspeakers (although you'll then need a large external battery for the phantom power if using a shotgun for more than half an hour).

Alternatively, a long shotgun mic, like the Rode NTG8.

I've done the same with an impact boom stand, but if you don't need the boom extension (or angle capabilities), then a straight 4m might do the trick. Impact Heavy Duty Light Stand, Black - 13' (4m) LS-13HB B&H