I think Strider [name_f]Sue[/name_f] works but if you want some other options:
LOTR
Siriondil [name_f]Sue[/name_f]
Samwell [name_f]Sue[/name_f]
Sirion [name_f]Sue[/name_f]
“Real” name options:
[name_m]Soren[/name_m] [name_f]Sue[/name_f]
[name_m]Salomon[/name_m] [name_f]Sue[/name_f]
Personally one syllable names sound a little to sing-song with the double S, I would stick with 2+.
I don’t think Strider’s a good name, and Stryder is just Strider misspelled. [name_m]How[/name_m] about [name_u]Sam[/name_u], if it must start with an S and be LOTR?
I would prefer names that have a long history of masculine use with [name_f]Sue[/name_f], or it runs the risk of sounding like a ‘unisex’ first name - [name_m]Sebastian[/name_m] [name_f]Sue[/name_f] is a great suggestion, and something like [name_m]Samuel[/name_m] [name_f]Sue[/name_f], [name_u]Sawyer[/name_u] [name_f]Sue[/name_f], [name_m]Scipio[/name_m] [name_f]Sue[/name_f], [name_m]Solomon[/name_m] [name_f]Sue[/name_f], [name_m]Seymour[/name_m] [name_f]Sue[/name_f], [name_m]Sholto[/name_m] [name_f]Sue[/name_f], [name_m]Siegfried[/name_m] [name_f]Sue[/name_f], Skandar [name_f]Sue[/name_f], [name_u]Spencer[/name_u] [name_f]Sue[/name_f] or [name_m]Stephen[/name_m] [name_f]Sue[/name_f] would be good too.