As a designer consider that there would be minimum quantities imposed by the manufacturer to cover special setup and organisational costs. Such fabric would not be wanted by anyone else and so you would have to buy the fabric by the roll – anything from 20m to 200m. So, although possible, we generally advise against it.
There are also more detailed reasons. From a manufacturing point of view it is very hard to guarantee a match to the colour you have – some dyes are better than others, so fabrics TAKE dyes better than others. Sometimes you know the exact original colour and other times not. Sometimes the fabric you are trying to match to might have a pile – so even if you workout a textile pantone colour, what exactly are you measuring? The fabric will look differently coloured from different angles.
The fabric you have may well have faded since purchase and there will be colour tolerances in what a manufacturer can produce from new. You would also have to consider that new and old would wear and fade differently – so there are many sources of ‘error’ or colour variation. Therefore our experience (from other manufacturers it’s the same) is that an exact match is rarely achieved and then the client/manufacturer relationship could be spoilt and a lot of time wasted by both parties.