Well Aurora is long gone but the molds are still in existance. The Silver, Blue Red and Black Knights have been reappearing at irregular intervals over the decades. The rare Gold Knight of Nice has not been seen in hobby shops for at least 40 years. Ran across this tidbit recently- http://www.culttvmanshop.com/Auroras-Gold-Knight-reissue-from-Revell--PREORDER-RESERVATION_p_1523.html
Price seems to be a little higher than its 50's, $1.98 debute ;D