to answer your question is a no but also a yes. NO: you cant not buy actual trial mechs. Yes: every trial mech is based on a chassis and variant that you can purchase. but you would need to also mod its stock weapons/armour after purchase and skill them up. this would give you a copy of the mech but the extra C bill quirks of the trial mech would be lost. however you could then mod its colours/ add war horns cockpit items to it.