According to pathfinder rules it would cost 8000 gold to make those boots spell lvl x caster lvl x 2000g then you multiply the cost by 4 because it is a round per lvl spell. so
1(spell lvl) x 1(caster lvl) x 2000g= 2000g x 4(round per lvl to continuous) = 8000 gold plain and simple Table 15-29 in your core
