The Pilgrims travel to Brackley Town on Good Friday (kick-off 3.00pm) ahead of their final home fixture on Easter Monday against Ashton United.
Bradford City loanee Clare and fellow striker Slew, who netted for the Pilgrims in their 3-1 home defeat to Brackley earlier in the campaign, both missed last Saturday's 2-0 defeat to Darlington through illness.
Elliott is confident that the duo will be available — but is less hopeful about the potential inclusion of top goalscorers Gavin Allott (thigh) and Nicky Walker (knee).
United centre-half Ryan Cresswell (neck) will also be checked after missing the Darlington clash.
Brackley secured their play-off position with a last-gasp 2-1 win at Altricham on Tuesday evening to earn themselves a third shot at promotion following promotion final defeats to FC Halifax Town in 2013 and Harrogate Town in 2018.
The Pilgrims were beaten 4-1 by the Saints in last season's corresponding fixture.
Good Friday's match referee is Matt Corlett, who has taken charge of United's 2-0 win at Altrincham in August and 4-1 defeat at Chester FC in February.
POSTCODE FOR SAT NAV: NN13 7EJ.
BUSA COACH DEPARTURE: 11.15am.
UNITED COLOURS: Purple.
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