Hello there ladies and gents! Nice to be here

I am a Maya 2013 (among others) animator working on a 2010 laptop. I'm currently working on a freelance project and the scenes I'm animating are around 300 mb. My laptop doesn't like this and I get a lot of lag, which makes animating very slow and annoying. Is this scene size something usual?
My laptop specs are: Intel Core 2 @2.13GHz witn 8gb RAM, Win7 64 and ATI Mobility Radeon 4600.
My question is, would you suggest I bought a new laptop? I guess what I need is a gaming laptop with a strong graphics card?
I'd go for a stationary, but I don't know where I'm gonna be the next few months.

I'd buy a new computer probably without too much thought if I was freelancing on a steady basis from home, but since I have a full time job at a studio, I don't know how often these freelance gigs will keep coming and if I got time for them. Bottom line is, I'm afraid I'm gonna invest on something that I might not make heavy use of and that it will quickly become obsolete.

Thoughts? Suggestions on new laptop?

Thanks for your time