Unless you have any micro-groove records, you should be able to use any modern mono cartridge with a spherical, elliptical or fine line stylus. A true mono cartridge like the Denon DL-102 will provide you with 1-channel "true mono" output if you are using a single channel system.
If you will be playing these LPs through your stereo system, a "dual mono" cartridge like the Ortofon 2M Mono, the new Quintet Mono or the Cadenza Mono will provide 2-channel mono output. Several manufacturers also offer these cartridges: Audio Technica, Grado Shelter and others.
*Disclaimer - I am an Ortofon dealer*
If you will be playing these LPs through your stereo system, a "dual mono" cartridge like the Ortofon 2M Mono, the new Quintet Mono or the Cadenza Mono will provide 2-channel mono output. Several manufacturers also offer these cartridges: Audio Technica, Grado Shelter and others.
*Disclaimer - I am an Ortofon dealer*