Send 1,000 hunting rifles with mil-dot scope, 500 rounds each, and 1,000 mil-dot reticle spotting scopes. Teach 2,000 people how to shoot (3 weeks), how to hide (2 weeks), how to navigate (1 week) and basic first aid (1 week). Assume one week to in-process. In 8 weeks, you can field 1,000 basic sniper teams.
In 6 months, you would have somewhere in the neighborhood of 2,500 sniper teams (assuming some losses). If these sniper teams took 1 shot and wounded or killed 1 combatant per day, in 1 month the losses to the Russian / separatist forces would be enormous. I am of the opinion that after 2 months, the Ukrainians would be running out of targets.
Interestingly, artillery has so far played the dominant role in Ukraine, killing more soldiers and destroying far more tanks and vehicles (all types) than my beloved infantry. We used to believe that the old Soviet firing tables were overly optimistic in their estimated effects against armor, but concentrated artillery fire with conventional rounds has proven to be absolutely devastating against Ukrainian tanks and other armored vehicles. (In other words, direct hits are not required since shards bursting at 20m+ are penetrating tanks' top and side armor.) And as a side note, tactical air power has thus far been virtually nonexistent.
Neither side in Ukraine is suffering any shortage of weapons, ammunition or military training. Ukraine is filled with vast stores of Soviet era everything and is itself a major arms manufacturer and exporter. And its population has a high percentage of military veterans dating back to the old days of universal conscription. So far, it appears the key difference on the battlefield has been motivation, leadership and will. Kiev's conscript army is not faring well, and its rates of draft avoidance and desertion are high and growing.
A recent report from the Atlantic Council, the Brookings Institution, the Center for a New American Security, and the Chicago Council on Global Affairs listed what they think Ukraine needs.
http://www.thechicagocouncil.org/ukraine
“Additional non-lethal assistance should include: counterbattery
radars, unmanned aerial vehicles (UAVs),
electronic counter-measures for use against opposing
UAVs, secure communications capabilities, armored
Humvees and medical support equipment.
Lethal defensive military assistance should include light
anti-armor missiles, given the large numbers of armored
vehicles that the Russians have deployed in Donetsk and
Luhansk and the abysmal condition of the Ukrainian
military’s light anti-armor weapons.”
Eh, did you see the vid where one of the Russians, er, separatist leaders is talking to a camera, and a guy a few feet behind him gets whacked by a sniper. Talker never even winces - just keeps talking to the camera.
The Russians (er, separatists) have a big qualitative edge in weaponry. Snipers are not going to stop tanks. However, I think snipers could do damage behind the lines, if they have the guts to view themselves as expendable, and go after high value targets...