Old mountain bike - replacing crank.
Hi all. I've got a mountain bike that's getting on a bit - try 12 years old or thereabouts. There's now a lot of play in the crank and recently it's started creaking. The internet doesn't seem very forthcoming with piccies etc about different (old) crank types and the whether they can be replaced or are now totally obsolete etc. So... the bike itself is an Emmelle 'Cortina' with a 300lx groupset. The parts of the crank/bottom bracket that I can make out include a 14mm hex nut that is recessed into the crank end of both pedals and two metal washers (?) that are fitted either side of the bottom bracket shell. Theses are slightly larger in diameter than the shell, have crenellated edges and each has two square notches cut into them that are diametrically opposed.
Now then - can anyone tell me what on earth I've got, whether it can be serviced or even if you can get a replacement for whatever type of crank it is?