There is a Battle CD on Pokemon XD which uses a Roaring Exploud and two Slaking, so it's similar enough to Hyper Beam for what you're suggesting. The idea itself is powerful, but fiddly to pull off and a lot more effort than you need.
However, if you're determined to use it, may I make a few suggestions?...
Slaking@Choice Band
Nature: Adamant
EV: 80 HP/252 Att/60 Def/100 Speed/12 Sp Def
Trait: Truant
Hyper Beam
Shadow Ball
Earthquake/Protect
Rock Slide/Protect
Couldnt resist.
Skarmory@Leftovers
EV: 252 HP/56 Att/200 Def
Nature: Impish
Trait: Sturdy
Drill Peck
Roar
Steel Wing/Rest
Spikes/Rest/Protect
Spikes is bleh in 2 v 2, but could be funny.
Gengar@Lum Berry
Nature: + Sp Att, - Def
EV: 252 Speed/252 Sp Att/6 Att
Trait: Levitate
Skill Swap/Psychic/Giga Drain
Thunderbolt/Ice Punch/Psychic
Destiny Bond/Psychic/Ice Punch/Giga Drain
Explosion
Skill Swap Slaking is an option if you want to mix and match.
Hariyama@Focus Band
Nature: Adamant
EV: 212 HP/144 Att/60 Def/72 Sp Def
Trait: Thick Fat
Whirlwind
Arm Thrust/Brick Break
Fake Out/Protect
Protect/Rock Slide/Earthquake
I dunno, I've been using this guy a lot ingame lately, a lot more fun than I first gave credit for. Secondary option for protecting your Hyper Beamer.