The german sniper has about the same survival chance against small arms fire as the soviet sniper team.
The high armor value of the german sniper means that statistically his survival is very RNG dependent (yeah!).
So he can die from the first volley of an engineer squad at long range as well as survive retreating right through 2 conscript squads - if RNG wills it.
... resulting in occasional bouts of rage on both sides
Attempt at a 'short' summary:
T70
Easily the most effective counter. Impossibly high accuracy even against retreating units.
Just be wary of fausts and bide your time for a good flank.
Scout car
Even without a unit inside it has about the same AI as the german 221. If it gains vet it can easily blitz a sniper unless fausted (bide your time and flank).
Mortars (especially the 120mm)
Killing the german sniper by barraging his suspected position is feasible and yet requires luck (less so with the 120mm due to the mortars range and large AoE).
Not a hard counter - but will force some retreats and will put a constant mirco drain on your opponent possibly forcing mirco mistakes on other units.
ZIS Barrage
The ZIS Barrage is deadly as it fires instantly and has very little air time. Best used defensively.
Artillery (Howitzers and Katjuscha)
Basically the same as the mortars - much higher chance of success though.
Mines
If a german sniper triggers one he's dead. Even a lot of good players get to cocky and trigger one of these
Seriously, they almost always pay off even if there is no sniper on the field.
Countersniping
Get your own sniper team and try to lure the german sniper into range while cloaked. As you stated hard to pull off and needs quite a bit of planning but works like a charm.
Even if the attempt fails the german player will get more cautious (and paranoid) about his sniper thus reducing the MP drain inflicted to your army.
Consrips Orahh! bumrush
This
will not kill the german sniper unless your opponent fucks up.
However, it will force a retreat if you bumrush him - not bad for 10 munis. Just do not run straight into PGrens or LMG grens while charging.
Flank and force retreat
Position a squad in the snipers retreat path (Orahh! helps just remember: Consrips who Orahh! do not fire while moving!)
Force the german sniper to retreat (...somehow)
Easy, right
/irony