When I recapped my PSU of SE/30,Capacitor shop in Tokyo(Akihabara) said some Voltage-Rating was eliminated.so you might not be able to find same capacitance-voltage capacitor.but you can use higher voltage-rating ones(ex. 16V -> 25V).Usually voltage-rating gets higher,body of capacitor gets larger,may not fit into board.but capacitor I got were slimmer than 1/4 centuries ago.They were all low-impedance and 105C but not that expensive ones.