Sadly no. Lapras isn't worth powering up or using a TM on (unless you've got lots of CTM's), which sucks. SUCKS. I think the best time I had playing Pokémon Go was when I arrived home a 11pm after a long day, pulled my phone out of my pocket and there was a Lapras in my front yard. (Turned out to be an 84% IV with Ice/Ice.) I love my Lapras.
But it's not useful right now.
I am in a similar situation. Hatched a 98% snorlax; 15/14/15. Have around 60 candies but already have a 3000CP snorlax.
I might power up if flush on dust but as I just powered up a gengar to lvl 35 Snorlax is on hold. I know all about slaking and snorlax has no real use but it's one of my favorite pokemons so I will power up, just not now.
I am on a similar situation the difference is that I got the 96% one FB/B from one of the first raids I did (the first week raid system came out).
Lapras here is ULTRA rare (I am level 39, only caught two in the wild thanks to water/ice events, never seen one out of events despite we have a decent amount of rare spawns like Dragonite, Togetic, Hitmontop, Snorlax...) and I really love her, so I made her my buddy and now I am finally near the end, I have 194 candies, thanks a lot to berry feeding system because I keep putting Lapras on gym and feed her berries to death xD (around 60 candies are from feeding). My advice is, if you have the candies and the dust power her up, if you don't have one or both resource, grind for them and power up when you get them.
I think patience is something that always gets you something in return in this game, who knows, maybe while you walk her of farm dust you get a 100% from a raid or an egg...