I saw some in Decathlon - seemed a bit cheaper than in tack shop. They also had a smart cheaper version which was EN1384 standard and about £45 - nearly bought one even though i didnt need it !!
Its probably just new horse syndrome plus the fact that you say he hasnt been ridden much by his last owner. He will probably get better as you get to know him and he gets used to it all over again. Be patient and lots of praise when he does what you want. Good Luck !!
My three are a bit wild as not much turnout either. Calmer added to feeds,lunging if necesary before attempting to get on and not going out onto our 60mph main road until theyve stopped leaping around!! Roll on summer