某商场准备购进$A$,$B$两种书包,每个$A$种书包比$B$种书包的进价少$20$元,用$700$元购进$A$种书包的个数是用$450$元购进$B$种书包个数的$2$倍.请解答下列问题:
$(1)A$,$B$两种书包每个进价各是多少元?
$(2)$若该商场购进$B$种书包的个数比$A$种书包的$2$倍还多$5$个,且$A$种书包不少于$18$个,购进$A$,$B$两种书包的总费用不超过$5450$元,则该商场有哪几种进货方案?