Replacement of a church noticeboard is unlikely to require a formal faculty application as long as the materials, size and design are either a purely like-for-like with the old noticeboard or in line with the diocesan "standard" of white lettering on a dark blue (Pantone 2747) background.
You should consult your local planning department if you are proposing to change the design. This is particularly the case where you are increasing the size of a noticeboard, as your local authority may require you to apply for Advertising Consent if the new board would be over a certain size.
You will need to apply for a faculty for any entirely new noticeboard in a new location.
The Diocese does not maintain lists of approved contractors. However, one firm which has installed noticeboards to many churches, and whose website you may find helpful, is The Church Noticeboard Company. This company also produces Christian Unity signs such as "One Church. One Lord. Jesus Christ. Worship Him Here."