ferroburak,

I have used jojoba and olive oil in various proportions to enrich lather, and also for use in the 'oil pass' when using safety razors.

jojoba/olive/castor and other oils seem to perform very similarly, so take your pick and give it a whirl

Mr Ham ('LeisureGuy') has given a formula in his book (Leisureguy's Guide to Gourmet Shaving: Shaving Made Enjoyable); this has the benefit of you being able to eat the remaining stock oils

2 parts Almond oil
2 parts Avocado oil
2 parts Olive oil
1 part Grapeseed oil
1 part Macadamia nut oil
1-2 drops essential oil(s) (for fragrance)—or however much you want

Have fun !

Best regards

Russ