insert custom taxonomy into javascript

i got a simple javascript to display a future time. the script is executed from post's content.

    <script type="text/javascript">
<!--
var currentTime = new Date()
currentTime.setMinutes(currentTime.getMinutes() + 30) */Ready Minutes*/
currentTime.setHours(currentTime.getHours() + 5) */Ready Hours*/
var month = currentTime.getMonth() + 1
var day = currentTime.getDate()
var year = currentTime.getFullYear()
document.write(day + "/" + month + "/" + year)
//-->
</script>

it displays a date and time + whatever value i set in (30)minutes and (5)hours. id like to use a custom taxonomy instead of these values for easier post edit if i need to update it to different value

so something like this:

currentTime.setMinutes(currentTime.getMinutes() + <ready_minutes_taxonomy>) */Ready Minutes*/

is this even possible? thank you in advance!