Replace Token Solution for abbreviates that are part of other words

I am working on a text analysis. There are abbreviations in my original text, such as cust or cust. for customer. I can put the replace token operator before the tokenize operator and enter multiple replacements such as replace cust space with customer and cust. with customer, but I am curious if there is a way to do it after the tokenization because it has "grouped" the cust abbreviations together. I did try placing the replace operator after tokenization but it replaced all occurrences of cust with customer, including the full word customer. Any thoughts/ideas?  thank you for your help.