I recomend buying a starter set from webshop, then you get the Sinkadus and the Z12 Barbarella, both items are very good at low levels.
Alternatives on low levels:
1 pts DMG:
- B101(L) looted, MU to high imho to make it eco
- Rookie Laser amp(L) mission
2 pts DMG:
- Road.Monkey Laser Amp MK I(L) crafted
- Sheer XR40(L) crafted
- ZX Sinkadus webshop starter pack (repairable)
3 pts DMG:
- Omegaton A101 looted, very high markup, but repairable, it may pay if you use it a lot, compared to L amps (long run)
4 pts DMG:
- Boom CCC(L) looted
- Hotfood 5(L) crafted
5 pts DMG:
- Muzwed Energie Amp V1(L) looted, actually no clue what planet
sorry
- SheerXR50(L) crafted
7 pts DMG:
- E-Amp 11 crafted (uneco)
- Omegaton A102 looted
- Omegaton A201 looted (old , doesn´t drop anymore) - better eco than A102, but much higher MU
- Teenie Weenie Laser Amp MKII(L) crafted
Hint:
to be eco and not overamp, your weapon should have 2xMax DMG than the amp adds, so for a 7 DMG amp, you should use it on weapon with max DMG 14+
Best eco sets repairable:
Bukins Rifle + ZX Sinkadus
Z12 Barbarell + ZX Sinkadus or A101
Ozpyn Chon S1X1 + ZX Sinkadus or A101
There is some other not that easy available options, so I let that aside.
Hint2:
Never buy Solomate Opallo, its not really eco anymore and you will do better with L rifle from TT and even more better with Z12 from starter pack (webshop) for less MU