Fairly common for the GasGas swingarm to break where the bolt for the brake caliper goes through it, so not unlikely for it to have been changed but it would be a direct replacement between a standard model and the Raga.
GasGas from that era had Marzocchi forks, fairly certain the Raga was no different.
Standard GasGas had a Dellorto carb - Raga I think had the Keihin so there would have been an adaptor or different rubber between airbox and Carby. Nice use of an innertube by the previous owner.
Anything GasGas from 02 to 08 should fit, into 09 the frame changed so there might be differences.