Motorcycle Questions and General Hangout

on a side note - how do you assess well the number of spare parts left over for any given motorcycle? I’m just curious as I kinda love the DT125 / TT250R (and honestly the VR150 might even be ok if it’s old Hartford) and would love to get one as a cheap weekend offroader so I don’t destroy my new bike, but I do think the parts situation is probably getting tighter for those… Is there any way to get a good frame on that?

Or do I just avoid that money and time pit and keep riding current bike / get a beat up CRF150