a 5 in pleated filter will cause more less restriction than a 1 in pleated filter. do you have a return grill or is your filter in the filter rack on the air handler? if you have filters in the return grills you may be able to use something like this https://www.amazon.com/FilterBuy-Honeywell-FC40R1060-FC35A1092-Compatible/dp/B07RYZX55Q and be able to use a 5" filter without changing the duct work